A YANG Data Model for In-Situ
OAMHuawei156 Beiqing Rd.Beijing100095Chinazhoutianran@huawei.comFutureweiUnited States of Americajames.n.guichard@futurewei.comCisco SystemsHansaallee 249, 3rd FloorDuesseldorfNordrhein-Westfalen40549Germanyfbrockne@cisco.comCisco SystemsTril Infopark Sez, Ramanujan IT CityNeville Block, 2nd floor, Old Mahabalipuram RoadChennaiTamil Nadu600113Indiasrihari@cisco.comIPPMIn-situ Operations, Administration, and Maintenance (IOAM) records
operational and telemetry information in user packets while the packets
traverse a path between two points in the network. This document defines
a YANG module for the IOAM function.In-situ Operations, Administration, and Maintenance (IOAM) records OAM information within user
packets while the packets traverse a network. The data types and data
formats for IOAM data records have been defined in . The IOAM data can be embedded in
many protocol encapsulations such as Network Services Header (NSH) and
IPv6.This document defines a data model for IOAM capabilities using the
YANG data modeling language. This YANG
model supports five IOAM options, which are:Incremental Tracing Option
Pre-allocated Tracing
OptionDirect Export
OptionProof of Transit (PoT)
OptionEdge-to-Edge
OptionThe keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP14,
, when, and only when,
they appear in all capitals, as shown here.The following terms are defined in and are
used in this specification: augmentdata modeldata nodeThe terminology for describing YANG data models is found in
.Tree diagrams used in this document follow the notation defined in
.The IOAM model is organized as list of profiles as shown in the
following figure. Each profile associates with one flow and the
corresponding IOAM information.The "ioam-info" is a container for all the read only assistant
information, so that monitoring systems can interpret the IOAM
data. /acl:acls/acl/aces/ace/name
+--rw protocol-type? ioam-protocol-type
+--rw incremental-tracing-profile {incremental-trace}?
| ...
+--rw preallocated-tracing-profile {preallocated-trace}?
| ...
+--rw direct-export-profile {direct-export}?
| ...
+--rw pot-profile {proof-of-transit}?
| ...
+--rw e2e-profile {edge-to-edge}?
...]]>In the "ioam-profiles", the "enabled" is an administrative
configuration. When it is set to true, IOAM configuration is enabled
for the system. Meanwhile, the IOAM data-plane functionality is
enabled.The "filter" is used to identify a flow, where the IOAM profile can
apply. There may be multiple filter types. ACL is a common way to specify a flow. Each
IOAM profile can associate with an ACE(Access Control Entry). IOAM
actions MUST be driven by the accepted packets, when the matched ACE
"forwarding" action is "accept".The IOAM data can be encapsulated into multiple protocols, e.g.,
IPv6 and NSH. The "protocol-type" is used
to indicate where the IOAM is applied. For example, if the
"protocol-type" is IPv6, the IOAM ingress node will encapsulate the
associated flow with the IPv6-IOAM format.IOAM data includes five encapsulation types, i.e., incremental
tracing data, preallocated tracing data, direct export data, proof of
transit data and end to end data. In practice, multiple IOAM data
types can be encapsulated into the same IOAM header. The
"ioam-profile" contains a set of sub-profiles, each of which relates
to one encapsulation type. The configured object may not support all
the sub-profiles. The supported sub-profiles are indicated by 5
defined features, i.e., "incremental-trace", "preallocated-trace",
"direct export", "proof-of-transit", "edge-to-edge".The IOAM tracing data is expected to be collected at every node
that a packet traverses to ensure visibility into the entire path a
packet takes within an IOAM domain. The preallocated tracing option
will create pre-allocated space for each node to populate its
information . The "preallocated-tracing-profile" contains the detailed
information for the preallocated tracing data. The information
includes:enabled: indicates whether the preallocated tracing profile is
enabled.node-action: indicates the operation (e.g., encapsulate IOAM
header, transit the IOAM data, or decapsulate IOAM header) applied
to the dedicated flow.use-namespace: indicate the namespace used for the trace
types.trace-type: indicates the per-hop data to be captured by the
IOAM enabled nodes and included in the node data list.Loopback mode is used to send a copy of a packet back towards
the source.Active mode indicates that a packet is used for active
measurement.The incremental tracing option contains a variable node data fields
where each node allocates and pushes its node data immediately
following the option header. The "incremental-tracing-profile"
contains the detailed information for the incremental tracing data.
The detailed information is the same as the Preallocated Tracing
Profile, but with one more variable, "max-length", which restricts the
length of the IOAM header.The direct export option is used as a trigger for IOAM nodes to
export IOAM data to a receiving entity (or entities). The
"direct-export-profile" contains the detailed information for the
direct export data. The detailed information is the same as the
Preallocated Tracing Profile, but with one more optional variable,
"flow-id", which is used to correlate the exported data of the same
flow from multiple nodes and from multiple packets.The IOAM Proof of Transit data is to support the path or service
function chain verification use cases. The "pot-profile" contains the
detailed information for the proof of transit data. "pot-type"
indicates a particular POT variant that specifies the POT data that is
included. There may be several POT types, which have different
configuration data. To align with , this document only defines IOAM
POT type 0. User need to augment this module for the configuration of
a specifc POT type.The IOAM edge to edge option is to carry data that is added by the
IOAM encapsulating node and interpreted by IOAM decapsulating node.
The "e2e-profile" contains the detailed information for the edge to
edge data. The detailed information includes:enabled: indicates whether the edge to edge profile is
enabled.node-action is the same semantic as in Section 2.2.use-namespace: indicate the namespace used for the edge to edge
types.e2e-type indicates data to be carried from the ingress IOAM
node to the egress IOAM node. file "ietf-ioam@2022-07-07.yang"
module ietf-ioam {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-ioam";
prefix "ioam";
import ietf-access-control-list {
prefix "acl";
reference
"RFC 8519: YANG Data Model for Network Access Control
Lists (ACLs)";
}
import ietf-interfaces {
prefix "if";
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-lime-time-types {
prefix "lime";
reference
"RFC 8532: Generic YANG Data Model for the Management of
Operations, Administration, and Maintenance (OAM) Protocols
That Use Connectionless Communications";
}
organization
"IETF IPPM (IP Performance Metrics) Working Group";
contact
"WG Web:
WG List:
Editor: zhoutianran@huawei.com
Editor: james.n.guichard@futurewei.com
Editor: fbrockne@cisco.com
Editor: srihari@cisco.com";
description
"This YANG module specifies a vendor-independent data
model for the In Situ OAM (IOAM).
Copyright (c) 2021 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Simplified BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
revision 2022-07-07 {
description "First revision.";
reference "RFC XXXX: A YANG Data Model for In-Situ OAM";
}
/*
* FEATURES
*/
feature incremental-trace
{
description
"This feature indicated that the incremental tracing option is
supported";
reference "RFC 9197: Data Fields for In-situ OAM";
}
feature preallocated-trace
{
description
"This feature indicated that the preallocated tracing option is
supported";
reference "RFC 9197: Data Fields for In-situ OAM";
}
feature direct-export
{
description
"This feature indicated that the direct export option is
supported";
reference "RFC XXXX: In-situ OAM Direct Exporting";
}
feature proof-of-transit
{
description
"This feature indicated that the proof of transit option is
supported";
reference "RFC 9197: Data Fields for In-situ OAM";
}
feature edge-to-edge
{
description
"This feature indicated that the edge to edge option is
supported";
reference "RFC 9197: Data Fields for In-situ OAM";
}
/*
* IDENTITIES
*/
identity filter {
description
"Base identity to represent a filter. A filter is used to
specify the flow to apply the IOAM profile. ";
}
identity acl-filter {
base filter;
description
"Apply ACL rules to specify the flow.";
}
identity protocol {
description
"Base identity to represent the carrier protocol. It's used to
indicate what layer and protocol the IOAM data is embedded.";
}
identity ipv6 {
base protocol;
description
"The described IOAM data is embedded in IPv6 protocol.";
reference "RFC XXXX: In-situ OAM IPv6 Options";
}
identity nsh {
base protocol;
description
"The described IOAM data is embedded in NSH.";
reference
"RFC XXXX: Network Service Header (NSH) Encapsulation
for In-situ OAM (IOAM) Data";
}
identity node-action {
description
"Base identity to represent the node actions. It's used to
indicate what action the node will take.";
}
identity action-encapsulate {
base node-action;
description
"It indicates the node is to encapsulate the IOAM packet";
}
identity action-decapsulate {
base node-action;
description
"It indicates the node is to decapsulate the IOAM packet";
}
identity trace-type {
description
"Base identity to represent trace types.";
}
identity trace-hop-lim-node-id {
base trace-type;
description
"It indicates the presence of Hop_Lim and node_id in the
node data.";
}
identity trace-if-id {
base trace-type;
description
"It indicates presence of ingress_if_id and egress_if_id
(short format) in the node data.";
}
identity trace-timestamp-seconds {
base trace-type;
description
"It indicates presence of timestamp seconds in the node data.";
}
identity trace-timestamp-fraction {
base trace-type;
description
"It indicates presence of timestamp fraction in the node data.";
}
identity trace-transit-delay {
base trace-type;
description
"It indicates presence of transit delay in the node data.";
}
identity trace-namespace-data {
base trace-type;
description
"It indicates presence of name space specific data (short format)
in the node data.";
}
identity trace-queue-depth {
base trace-type;
description
"It indicates presence of queue depth in the node data.";
}
identity trace-checksum-complement {
base trace-type;
description
"It indicates presence of the Checksum Complement node data.";
}
identity trace-hop-lim-node-id-wide {
base trace-type;
description
"It indicates presence of Hop_Lim and node_id in wide format
in the node data.";
}
identity trace-if-id-wide {
base trace-type;
description
"It indicates presence of ingress_if_id and egress_if_id in
wide format in the node data.";
}
identity trace-namespace-data-wide {
base trace-type;
description
"It indicates presence of IOAM-Namespace specific data in wide
format in the node data.";
}
identity trace-buffer-occupancy {
base trace-type;
description
"It indicates presence of buffer occupancy in the node data.";
}
identity trace-opaque-state-snapshot {
base trace-type;
description
"It indicates presence of variable length Opaque State Snapshot
field.";
}
identity pot-type {
description
"Base identity to represent Proof of Transit (PoT) types.";
}
identity pot-type-0 {
base pot-type;
description
"The IOAM POT Type field value is 0, and POT data is a 16
Octet field to carry data associated to POT procedures.";
}
identity e2e-type {
description
"Base identity to represent e2e types";
}
identity e2e-seq-num-64 {
base e2e-type;
description
"It indicates presence of a 64-bit sequence number.";
}
identity e2e-seq-num-32 {
base e2e-type;
description
"It indicates the presence of a 32-bit sequence number.";
}
identity e2e-timestamp-seconds {
base e2e-type;
description
"It indicates the presence of timestamp seconds representing
the time at which the packet entered the IOAM-domain";
}
identity e2e-timestamp-fraction {
base e2e-type;
description
"It indicates the presence of timestamp fraction representing
the time at which the packet entered the IOAM-domain.";
}
identity namespace {
description
"Base identity to represent the Namespace-ID.";
}
identity default-namespace {
base namespace;
description
"The Namespace-ID value of 0x0000 is defined as the
Default-Namespace-ID and must be known to all the nodes
implementing IOAM.";
}
/*
* TYPE DEFINITIONS
*/
typedef ioam-filter-type {
type identityref {
base filter;
}
description
"It specifies a known type of filter.";
}
typedef ioam-protocol-type {
type identityref {
base protocol;
}
description
"It specifies a known type of carrier protocol for the IOAM
data.";
}
typedef ioam-node-action {
type identityref {
base node-action;
}
description
"It specifies a known type of node action.";
}
typedef ioam-trace-type {
type identityref {
base trace-type;
}
description
"It specifies a known trace type.";
}
typedef ioam-pot-type {
type identityref {
base pot-type;
}
description
"It specifies a known pot type.";
}
typedef ioam-e2e-type {
type identityref {
base e2e-type;
}
description
"It specifies a known e2e type.";
}
typedef ioam-namespace {
type identityref {
base namespace;
}
description
"It specifies the supported namespace.";
}
/*
* GROUP DEFINITIONS
*/
grouping ioam-filter {
description "A grouping for IOAM filter definition";
leaf filter-type {
type ioam-filter-type;
description "filter type";
}
leaf ace-name {
when "derived-from-or-self(../filter-type, 'ioam:acl-filter')";
type leafref {
path "/acl:acls/acl:acl/acl:aces/acl:ace/acl:name";
}
description "The Access Control Entry name is used to
refer to an ACL specification.";
}
}
grouping encap-tracing {
description
"A grouping for the generic configuration for
tracing profile.";
container trace-types {
description
"It indicates the list of trace types for encapsulation";
leaf use-namespace {
type ioam-namespace;
description
"It indicates the name space used for encapsulation";
}
leaf-list trace-type {
type ioam-trace-type;
description
"The trace type is only defined at the encapsulation node.";
}
}
leaf enable-loopback-mode {
type boolean;
default false;
description
"Loopback mode is used to send a copy of a packet back towards
the source. The loopback mode is only defined at the
encapsulation node.";
}
leaf enable-active-mode {
type boolean;
default false;
description
"Active mode indicates that a packet is used for active
measurement. An IOAM decapsulating node that receives a
packet with the Active flag set in one of its Trace options
must terminate the packet.";
}
}
grouping ioam-incremental-tracing-profile {
description
"A grouping for incremental tracing profile.";
leaf node-action {
type ioam-node-action;
description
"This object indicates the action the node need to
take, e.g. encapsulation.";
}
uses encap-tracing {
when "derived-from-or-self(node-action,
'ioam:action-encapsulate')";
}
leaf max-length {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
type uint32;
units bytes;
description
"This field specifies the maximum length of the node data list
in octets. The max-length is only defined at the
encapsulation node, and it's only used for the incremental
tracing mode.";
}
}
grouping ioam-preallocated-tracing-profile {
description
"A grouping for incremental tracing profile.";
leaf node-action {
type ioam-node-action;
description "This indicates what action the node will take,
e.g. encapsulation.";
}
uses encap-tracing {
when "derived-from-or-self(node-action,
'ioam:action-encapsulate')";
}
}
grouping ioam-direct-export-profile {
description
"A grouping for direct export profile.";
leaf node-action {
type ioam-node-action;
description "This indicates what action the node will take,
e.g. encapsulation.";
}
uses encap-tracing {
when "derived-from-or-self(node-action,
'ioam:action-encapsulate')";
}
leaf flow-id {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
type uint32;
description
"A 32-bit flow identifier. The field is set at the
encapsulating node. The Flow ID can be uniformly assigned
by a central controller or algorithmically generated by the
encapsulating node. The latter approach cannot guarantee
the uniqueness of Flow ID, yet the conflict probability is
small due to the large Flow ID space.flow-id is used to
correlate the exported data of the same flow from multiple
nodes and from multiple packets.";
}
}
grouping ioam-e2e-profile {
description
"A grouping for edge-to-edge profile.";
leaf node-action {
type ioam-node-action;
description
"It indicates how the node acts for this profile";
}
container e2e-types {
when "derived-from-or-self(../node-action,
'ioam:action-encapsulate')";
description
"It indicates the list of e2e types for encapsulation";
leaf use-namespace {
type ioam-namespace;
description
"It indicates the name space used for encapsulation";
}
leaf-list e2e-type {
type ioam-e2e-type;
description
"The e2e type is only defined at the encapsulation node.";
}
}
}
grouping ioam-admin-config {
description
"IOAM top-level administrative configuration.";
leaf enabled {
type boolean;
default false;
description
"This object is to control the availability of configuration.
It must be true before anything in the
/ioam/ioam-profiles/ioam-profile subtree can be edited.
If false, any configuration in place is not used.";
}
}
/*
* DATA NODES
*/
container ioam {
description "IOAM top level container";
container ioam-info {
config false;
description
"Describes assistant information such as units or timestamp
format. So that monitoring systems can interpret the IOAM
data.";
leaf timestamp-type {
type identityref {
base lime:timestamp-type;
}
description
"Type of timestamp, such as Truncated PTP or NTP.";
}
list available-interface {
key "if-name";
description
"A list of available interfaces that support IOAM.";
leaf if-name {
type if:interface-ref;
description "This is a reference to the Interface name.";
}
}
}
container ioam-profiles {
description
"Contains a list of IOAM profiles.";
container admin-config {
description
"Contains all the administrative configurations related to
the IOAM functionalities and all the IOAM profiles.";
uses ioam-admin-config;
}
list ioam-profile {
key "profile-name";
description
"A list of IOAM profiles that configured on the node.
There is no mandatory type of profile (e.g.,
incremental-trace, preallocated-trace.) in the list.
But at least one profile should be added.";
leaf profile-name {
type string{
length "1 .. max";
}
description
"Unique identifier for each IOAM profile";
}
container filter {
uses ioam-filter;
description
"The filter which is used to indicate the flow to apply
IOAM.";
}
leaf protocol-type {
type ioam-protocol-type;
description
"This item is used to indicate the carrier protocol where
the IOAM is applied.";
}
container incremental-tracing-profile {
if-feature incremental-trace;
description
"It describes the profile for incremental tracing option";
leaf enabled {
type boolean;
default false;
description
"When true, apply incremental tracing option to the
specified flow identified by the filter.";
}
uses ioam-incremental-tracing-profile;
}
container preallocated-tracing-profile {
if-feature preallocated-trace;
description
"It describes the profile for preallocated tracing option";
leaf enabled {
type boolean;
default false;
description
"When true, apply preallocated tracing option to the
specified flow identified by the following filter.";
}
uses ioam-preallocated-tracing-profile;
}
container direct-export-profile {
if-feature direct-export;
description
"It describes the profile for direct-export option";
leaf enabled {
type boolean;
default false;
description
"When true, apply direct-export option to the
specified flow identified by the following filter.";
}
uses ioam-direct-export-profile;
}
container pot-profile {
if-feature proof-of-transit;
description
"It describes the profile for PoT option";
leaf enabled {
type boolean;
default false;
description
"When true, apply Proof of Transit option to the
specified flow identified by the following filter.";
}
leaf pot-type {
type ioam-pot-type;
description
"The type of a particular POT variant that specifies
the POT data that is included..";
}
}
container e2e-profile {
if-feature edge-to-edge;
description
"It describes the profile for e2e option";
leaf enabled {
type boolean;
default false;
description
"When true, apply edge-to-edge option to the
specified flow identified by the following filter.";
}
uses ioam-e2e-profile;
}
}
}
}
}
]]>The YANG module specified in this document defines a schema for data
that is designed to be accessed via network management protocols such as
NETCONF or RESTCONF. The lowest NETCONF layer is the secure
transport layer, and the mandatory-to-implement secure transport is
Secure Shell (SSH). The lowest RESTCONF
layer is HTTPS, and the mandatory-to-implement secure transport is TLS.The Network Configuration Access Control Model
(NACM) provides the means to restrict access for particular
NETCONF or RESTCONF users to a preconfigured subset of all available
NETCONF or RESTCONF protocol operations and content.There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the default).
These data nodes may be considered sensitive or vulnerable in some
network environments. Write operations (e.g., edit-config) to these data
nodes without proper protection can have a negative effect on network
operations. These are the subtrees and data nodes and their
sensitivity/vulnerability:/ioam/ioam-profiles/admin-configThe items in the container above include the top level administrative
configurations related to the IOAM functionalities and all the IOAM
profiles. Unexpected changes to these items could lead to the IOAM
function disruption and/ or misbehavior of all the IOAM profiles./ioam/ioam-profiles/ioam-profileThe entries in the list above include the whole IOAM profile
configurations which indirectly create or modify the device
configurations. Unexpected changes to these entries could lead to the
mistake of the IOAM behavior for the corresponding flows.RFC Ed.: In this section, replace all occurrences of 'XXXX' with the
actual RFC number (and remove this note).IANA is requested to assign a new URI from the IETF XML Registry. The following URI is
suggested:This document also requests a new YANG module name in the YANG Module Names registry with the following
suggestion:For their valuable comments, discussions, and feedback, we wish to
acknowledge Greg Mirsky, Reshad Rahman, Tom Petch and Mickey
Spiegel.This appendix is non-normative.tbd